Williams is known to have guest starred in "Greek" and played the role of Leo in "The Sisterhood of the Traveling Pants 2". His "Grey's" role is still unclear but according to THR he will be "sexy, confident" and according to TV Guide magazine, he is a "charismatic" caregiver.

Zehetner meanwhile played as the mind-controlling Eden McCain on "Heroes". Her role on "Grey's" would be a doctor who is "feisty, very smart and competitive". With her qualities, Zehetner is bound to butt-head with at least one of the characters.

Baker, who previously joined the short-lived series "Valentine", is tapped to portray the "nicest" of all three but may be the one with a nasty secret.